The Wurlitzer duplex frames are not cleaned very well by a tracker
bar pump.  You have to take the mechanism apart to clean the pouches
that operate as a switch between the two tracker bars.  These are
cut-out pouches.  You can put vacuum to this unit on the end where
two large nipples are located and try the tracker bar pump first.

However, I doubt your problem is in these cut out pouches.  Your
problem is more likely in the valves, which you can remove one at
a time and repair.  Use a test roll or make one.  Test rolls do make
life easier.

Don Teach
1610 E. Bert Kouns, Shreveport, LA 71105
318 798 6000